US1653617A

US1653617A - Magnetic starter

Info

Publication number: US1653617A
Application number: US667103A
Authority: US
Inventors: Brisbois Odilon
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-10-08
Filing date: 1923-10-08
Publication date: 1927-12-27
Anticipated expiration: 1944-12-27

Description

Dec, 27, 1927.

O. BRISBOIS mmmxc 512mm Filled. Oct. 8, 1925' 2 Sheets-Sheet 2 Paten ed Dec. 27, 1927.

1,653,617 UNIT'EDISTATES, PATENT OFFICE.

om oN Brussels, 01" CHICAGO, ILLINoIs.

MAGNETIC sran'rnn.

Application filed October 8, 1928. Serial No. 367,103.

This invention relates to a magnetic engine starter of that type in which the magnetic flux is utilized for shifting a displaced armature for bringing a driving member,

5 such as a pinion, ,into engagement with a driven member, such as a gear, upon the engine shaft.

Starting motors of this type have not been generally successful on account of their In high rate of speed at the time that the driving member is brought into meshing relation with the driven member. Many attempts have been made to decrease the speed of rotation during the period of engagement of the driving and driven member. Resistance coils have been used, and while they have met with some-success, the cost'of such coils is prohibitive. It has also been proposed to vary the angular relation of the brushes from their normal position, but for various reasons this scheme has hitherto been unsuccessful on account of the excessive sparking, short circuiting effects that would be made in the 7 2a the relative shifting of the brushes and commutators. While it seems unnecessary -to discuss all the other schemes that have ben attempted, it might be said that at the pres ent t1me,no one has perfected a practical 3 and commercial magnetic starter that has met the requirements of the automobile manufacturer. The few that are in use,einploy expensive resistance coils or systems, that are prohibitive except in the very high priced cars. 1 i F This invention is designed to overcome the above noted objections and aims to provide a practical and commercially successful magnetic starter, [that is inexpensive and 40 that can be used on any ordinary car. In

attaining these results, there hasbeen provided a magnetic starter in which the com-. mutator brushes are initially angularly displaced for decreasing'the meshing speed of the motor and in which the arrangement is such that a mechanical retardation or drag is effecteduto also lower the speed of rotation, in which the brushes travel longitudi- .nally with the move ents of the armature,

.in which the strong armature-displacing spring has been eliminated so that the total endwise torque is eifectiveto shift the armature, and. in which the movements of the armature are controlled man-automatic way through the operationv of the motor. 'With and the grooves commutator by these and other advantages in view which will become more apparent in the following description anddisclosures, this invention comprlses the novel mechanism and combi-' nations hereinafter described and more particularly pointed out and defined in the appended claims.

In the accompanying drawings which illustrate certain preferred embodiments of this invention andin which. similar reference numerals refer to similar features in, the different views:

On the drawings:

Figure 10 is an elevational view of the starting motor. V Figure 2 is an enlarged longitudinal section of the same showing parts in elevation, illustrating an end commutator.

Figure 3 is a front elevational view of the commutator brushes and supporting ring with the motor shaft and easing shown in section. I v

Figure 4 is'an enlarged part sectional and elevational view of the starting-motor.

Figure 5 is an enlarged fragmentary sec: tional view of the motor casing illustrating certain features of the invention.

Figure 6 is a front elevational view of the starting motor.

Figure 7 is an enlarged longitudinal section through a starting motor involving a modification of the invention. I

Figure 8 is a front elevational view of the brush ring showing, parts in section and involving the modified form of the invention. Y I

As shown on the drawings:

. In referring to the drawing, especially to Figures 1 to 6, there is illustrated a motor compri'sing the supporting casing 1 having aforward extended bea'ring 2 in which a shaft 3 is slidably mounted. A driving member 4 in the form of a small seven toothed pinion is secured upon this shaft. The armature 5 is supported upon a shaft 6 journalled in .the extended bearings and connectedto the "shaft 3. The rear end of the shaft 6'is reduced and slidably supported in a sufiiciently longbearing socket -7 in the central part of the rear end of the motor 0 sing. s

In the,first form of the i vention, the armature! 5- provided with a rearend commutator 18 against which a plurality of brushes 9 bear. p I v I supported in. suitable holders .110 and 1 These brushes areslidably 'of the inner periphery of the casing. The

holder 10 has a central hub 13 which is frictionally held upon the motor shaft between a collar 14 and a washer 15 abutting the end commutator. The outer ends of the brush holder 10,are welded or secured to the ring 12. The brush holders 11' have up per attaching brackets that are welded or secured to the ring 12. It is therefore obvious that shifting or rotating of the ring 12 will carry the brush holders and brushes therewith. Springs 16 secured upon the brush holders yieldingly urge the brushes against thd commutator.

A stud 17 (Figure 5) having a head 21 is secured in the ring 12, and a roller 17 is mounted upon said stud. This stud projects into an arcuate or curved slot 18 in the motor casing. The contour of this slot is best shown in Figure 4: and it will be noted that it extends rearwardly from its mostforward point and curves or extends in a direction opposite to the normal starting rotation of the armature as indicated by the arrow in said figure. Consequently as the motor is started and the armature is drawn inwardly, the stud 17 is constrained to follow the curved guide way in a direction opposite to the direction of rotation of the armature. In the position shown in Figure 4, the ring 12 is in such a position that the brushes are angularly displaced with respect to their normal operating position so that when the motor circuit is closed, the magnetic field produced by the armature WlIlClings is displaced an amout corresponding substantially to the angular displacement of the brushes. The result is that the magnetic force produced by the armature coils and which reacts upon the field flux to produce rotation of the. armature, tends to rotate the armature in both directions, with slightly unequal and opposite forces, the difference being sufficient to impart a slight rotation to the armature for meshing puroses. The magnetic flux however will longitudinally sliift the armature inwardly, causing the stud 17 to travel in the slot to gradually advancethe brush holding ring 12 to normal operating position. While this ad vancing movement of the brushes will tend I to increase the rotation of the armature, it

will be appreciated that the opposite direction of rotation of the brushes caused by the stud 17 traveling in such opposite direction in the slot 18, will effect a braking action, retardation or drag upon the rotation of the armature. As the rotational "torque of the motor is not very great during such movement of the brushes, it will be appreciated that such a brakingaction may be appreciably effective in reducing the meshing speed of'the' armature. In order to retain the stud 17 in either end of the slot, some yielding means should be provided. In the present exemplification of this invention I have illustrated a double ended yielding detent member 1.9 (Figure 5) which is adapted to be secured so as to overlie the curved or spiral slot 18. Adjacent each end of said member, there is a downwardly projecting hump or shoulder 20 that lies in the path of movement of the head 21 of the stud 17, and which will yield upwardly allowing the stud to pass during the operation of the motor, very little effort being required to cause a yielding of the detent. These shoulders are spaced a suitable distance from the ends of the slot to confine the stud.

In Figure 7, there is shown a starting motor similar to the one just described except that it has radially extending brushes and the usual cylindrical commutator. In referring to said drawing, it will be observed that a ring 12 extends circumferentially of the inner periphery of the motor casing, this ring is provided with a stud 17 extending through a spiral slot 18 in the motor casing as shown in Figure 5. The ring 12 is integral with an apertured disk or spider 22 having a hub 23 which is frictionally confined on the shaft 6 between the collar 24 and the collar 25 adjacent the cylindrical commutator 26 on the motor shaft. A plurality of brush holders 27, four in the present instance, extend laterally from the disk. Brushes 28 are slidably mounted in these holders and-are yieldingly urged into contact with the commutator 26 through the springs 29 which are secured to' the ring 12". lVhile the operation of the starting motor can be clearly understood from the foregoing, a brief description will be given for the purpose of explaining the demeshing of the motor pinion and engine gear, and the control of the armature. hen the motor circuit is closed, the brushes are angularly displaced with respect to their normal operatingposition and the armature is longitudinally displaced with respect to its field. The magnetic flux will draw the armature inwardly since the same is designed to be displaced forwardly of its field. As the armature is drawn inwardly, it will rotate slightly' in the direction of tliearrows shown in Figures 5 and 6, and the stud 17 will be caused to travel rearwardly in the slot 18 in an opposite direction carrying the brushes therewith so that a drag or braking effect will be imparted to the armature shaft. lVhen the stud 17 reaches the opposite or rear end of the slot as viewed in Figure 4, the brushes will be in their normal operating position and the pinion 4 will have been brought into mesh with the usual engine gear for starting the engine, As soon as the engine has been started, and the motor circuit tate the armature,'and cause the stud 17 to travel forwardly in the slot to thereby shift the armature forwardly and demesli the pinionfrom the engine gear. vThis move- -ment is made possible-by the fact that the friction between the brushes and commutator is sufiicient to cause the brushes to rotate with the commutator on the armature and to overcome the opposed action of the stud in the cam slot.

From the foregoing, it will be apparentthe motor. It will also be appreciated that the elimination of the armature displacing spring that has usually been heretofore used affords a greater endwise torque for longi tudinally shifting the armature for bringing the gears into meshing relation, andthat the armature is automatically restored, thereby demeshing' the gears and the brushes are automatically displaced through the action imparted by the arcuat slot upon the brush holding ring afterthe motor circuit is closed. i

Iv am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I therefore do not purpose limiting the patent granted hereon. otherwise than necessitated by the prior art.

I I claim as my invention:

. 1. An engine starter comprising a motor having av normally displaced and shiftable armature, a commutator in connection with said armature, normally displaced brushes in contact with said commutator and shiftable therewith, and means for automatically rotating'said brushes relative to the armature during the shifting of the latter in one direction. i

2. The combination with an'electric start- I -ing lIlOtOIhfLVlIlg a longitudinally shiftable means armature and angularly shiftable commutam tor brushes, of means for automatically shifting said brushes during the longitudinal :movement of said armature'in a reverse directlon to. the normal rotation of said arma- H ture. s I

3. In an engine starter of the class described the combination wiwn electric mo- .tor having a longitudinall s iftable armature and angularly .shiftab ecommutator brushes movable with said armature, of

for automatically rotating said 7 brushes during ,theshifting movement of said armature when the motor is energized,

and longitudinally shifting said brushes with said armature when the motor is deenergized and mechanically rotated.

4. The combination with an engine member, of a starter therefor comprising an electric motor having a longitudinally shiftable armature adapted for operative connection with said engine member, said armature having rotatable commutator brushes, supported for shifting movement therewith, and mechanism for causing said brushes to rotate ina direction opposite to the rotation of the armature upon energizationof the motor for the purpose set forth.

5. The combination with an engine member, of a starter therefor comprising a motor ber, of a starter thereforcomprising a mo-' tor having a longitudinally shiftable armature havin means adapted to be brought into operative relation with said engine member, rotatable and shiftable commutator brushes for said armature, a holder for said brushes, and means havinga guide way receiving a part of said holder for controlling the rotation and shifting movements of said holder during the operation of said motor. 7. The combination with an engine member, of a starter therefor comprising a mo tor having a longitudinally shiftable armature provided with means adapted to be brought into operative relation with said engine member, a rotatable and longitudinally shiftable brush holder in connection with said armature automatically movable upon excitation of said motor and shiftable longitudinally upon de-energization of the motor for-shifting said armature and disconnect ing said means from the engine member.

8. The combinationwith an engine member, of a starter therefor comprising a motor having a longitudinally shift-able armature provided with means for engaging said engine member, a rotatable and longitudinally shiftable brush holder having a stud, means in connection with said motor providing a able for shifting said armature and disconnecting said means upon de-energization of the motor.

9. In an engine startlng motor, a longitudinally shiftable armature, a rotatable and longitudinally shiftabl'e commutator brush holder, means for automatically rotating said holder relative to the armature and longitudinally shifting the same with said armature when said motor is energized for start-" ing said engine, said means operating to shift said holder and armature to inoperative position when the motor is (lo-energized and driven by said engine.

10. The combinat1on with an engine member, of a starter therefor comprising a motor havin a lon itudinal] shiftable armature :1 o y .gine member, said holder being shifted longitudinally for shifting said armature when the motor is de-energized and its armature rotated by said engine member.

11. In an engine starting motor, a lon-- gitudinall y shiftable armature, a commutator brush holder mounted for rotation and longitudinal movement, means engageable with said holder for controlling its movements, whereby said holder will shift with said armature and rotate relatively thereto in an opposite direction when said armature moves in one direction, and will shift and rotate with said armature when the same is shifted in the other direction for the purpose described.

12. In a starter for an engine, a motor adapted to drive said engine, said motor having a shiftable armature normally displaced, and having a commutator brush holder mounted for predetermined rotation relative to said armature, and means actuated by the shifting of said arn'iature for rotating said brush holder for the purpose described.

In testimony whereof I have hereunto4 subscribed my name.

ODILON BRISBOIS.